Spirit Airlines enacted its controversial carry-on luggage policy this weekend, taking some customers by surprise and putting other airlines on watch.

On Sunday, the budget airline began charging passengers up to $45 for carry-on luggage.

Passengers who pay in advance during booking pay $30 for a carry-on bag. However, passengers who pay at the gate are charged a fee of $45. These charges are the same for domestic and international flights.

The airline does allow personal items that fit under the seat to be taken on for free. Spirit also does not charge for extra items such as umbrellas, cameras, infant diaper bags, assistive devices, outer garments, strollers, reading material, and wheelchairs.

In addition, members of Spirit’s special fare club pay a discounted $20 for a carry-on.Spirit is the first airline to charge passengers for carry-on items, a move it announced in April of this year. Though consumers have been paying for checked in baggage on most airlines for about two years, Spirit announcement to charge for carry-on bags was met with strong criticism.

Senator Charles Schumer (D-NY) felt so strongly about the new charges that he set out to counter the possibility the fees might spread to other airlines. Schumer extracted promises from American, Delta and other top five U.S. airlines to not charge for carry-on bags.

In anticipation of the new carry-on fee backlash, Spirit reduced its flying fares by about $40 on average, dropping its price for a one-way base fare to $63 on average for August.

According to a Spirit, the fee will be positive for both the airline and consumer, speeding up the check in process and allowing the airline to add more flights. With the reduced airfares, passengers will still be paying less to fly on Spirit, even with the carry-on fees, the airline has said.

Flying under the radar, however, are the airlines’ rising checked baggage rates, which also went up on Sunday.

For checked bags checked in at the gate, Spirit now charges $45 up from $25. Pre-checked in bags went up to $25 from $19, and there is an extra $5 charged to pre-checked bags on international flights.